American pop star Beyonce has given birth to twins, according to media in the US.
Entertainment Weekly, Us Weekly and People magazines confirmed the news, but the date of birth and gender of the babies are not yet publicly known.
Beyonce, 35, who is married to rapper Jay-Z, announced her pregnancy in an Instagram photo in February - the most-liked post in history on the network.
The couple already have a daughter, Blue Ivy, aged five.
There has been no official confirmation of the birth from Beyonce and Jay-Z themselves.
Other photos Beyonce posted after her pregnancy announcement showed her swimming under water, reclining on a bed of roses and sitting naked on a floral throne.
In one, the 'Lemonade' singer stood naked, cradling her belly with one hand and a breast with the other, next to the sculpted head of an Egyptian ruler.
Speculation about the twins' birth had grown in recent days after a woman was photographed entering a Los Angeles hospital on Friday holding a card that read "B + J".
Beyonce is the most-nominated star in the history of the Grammy awards, and her album Lemonade was the world's best-selling record of 2016.
She had been due to headline the Coachella music festival in California in April, but pulled out on her doctor's advice.
The twins' birth - if confirmed - comes only days after actor George Clooney and his wife Amal welcomed their own set of twins, Ella and Alexander.
The "Lemonade" singer, one of the most powerful women in the music business, announced the pregnancy on her Instagram account in February along with an image of her posed in lingerie and caressing a noticeable baby bump.
The announcement got more than 8 million "likes" in the first 24 hours to become the "most-liked" Instagram ever.
The R&B singer performed live at the Grammy awards in Los Angeles two weeks later, proudly displaying her swelling belly in a motherhood-themed show. She has since posted numerous pictures of her bare baby bump on her social media accounts.
The birth of Blue Ivy caused a paparazzi storm in 2012, with New York's Lenox Hill hospital shutting down part of its maternity wing to accommodate music's royal couple.
News of the pregnancy came less than a year after the release of
Beyonce's 2016 album "Lemonade," in which she appeared to address long-standing rumors of trouble in her eight-year marriage.
The lyrics of several songs spoke about being cheated on, and regretting being married. ButBeyonce
made clear in the final tracks of the album and in music videos featuring Jay-Z that she had decided to stay in the relationship.
The couple have never addressed the rumors publicly.